Adjustable size intumescent lined wall passthrough slot

ABSTRACT

Two slot forming components overlay through a pre-formed wall opening to form an adjustable wall passthrough slot. At least one slot surface has an intumescent layer of material positioned out of the way of documents passing through the slot. Heat from a fire will expand the intumescent material to fill the slot and prevent the spread of fire. Two inclined top and bottom slot surfaces are positioned in parallel and spaced apart by the desired thickness of the slot. A smoke shield flap of flexible fabric material hangs down within the slot to prevent the passage of smoke through the slot while allowing documents to pivot or push the smoke shield flap aside.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to wall pass-throughs and particularly to a wall passthrough slot for mail and paperwork, such as a patient record and mail receptacle for a healthcare office or other use, comprising a fire-rated slot having a depository opening in one side of the wall and a file receiving box on the opposite side of the wall which is preferably an adjustable slot to fit various wall sizes and accommodate variously sized items passed through; the slot having a smoke shield flap and an intumescent fire-stopping material lining on at least one slot surface for sealing the slot responsive to a fire to prevent the spread of fire through the wall.

2. Description of the Prior Art

Many fire-stopping devices are provided for electrical conduits that pass through walls. The devices prevent a fire from spreading through a wall where a hollow pipe or conduit passes through by using an intumescent material which essentially comprises a heat-expanding product, said intumescent material is applied about the hollow element, to exert thereon a radial pressure when exposed to fire to fill the pass through and prevent the spread of the fire through the pass through in the wall.

Prior art fails to provide a fire rated document depository slot through a wall.

U.S. Pat. No. 6,732,481, issued May 11, 2004 to Stahl, Sr., discloses an intumescent firestopping apparatus used in poke-through applications for selectively sealing an opening through a construction barrier such as a wall, floor or ceiling having cables or other penetrating members extending therethrough. The apparatus effectively seals this barrier responsive to a fire to prevent unwanted transmission of fire through conventional construction barrier areas. The apparatus includes a sleeve with two intumescent pads positioned therein. At least one of the pads has an arcuate curved central section to be biased against the other intumescent pad to define therebetween a confinement area for holding of cables centrally located therein in a dynamically adjustable sealing throat defined therebetween. These pads can be variously mounted with respect to the adjacent wall structures and one or both of the pads can be arched toward the other pad to facilitate defining of the dynamic throat for receiving cables extending therethrough.

U.S. Pat. No. 1,170,291, issued Feb. 1, 1916 to Link, describes a mail receptacle for use in association with a door or like structure with a mail chute. The mail receptacle mounted in proximity to the chute, for the purpose of catching the envelopes. The mail receptacle is provided with an adjustable front wall that is hinged to the base of the receptacle, said front wall may be opened to access the mail.

U.S. Pat. No. 4,538,389, issued Sep. 3, 1985 to Heinen, indicates a fire-break for passing at least one hollow element such as pipe, sleeve, or tube through a building wall, notably a partition or ceiling, which comprises a flange from substantially incombustible material which is mounted around said element.

U.S. Pat. No. 5,390,465, issued Feb. 21, 1995 to Rajecki, is for a device for installation in a building wall or floor to provide a passthrough opening for pipes, tubing, and the like includes an axially open first end and a second end closed by a transverse wall. A ring of intumescent material fills the axially open first end of the housing, and in one embodiment, a foam plastic filler material substantially fills the housing between the intumescent ring and the transverse wall. The intumescent ring can be provided with a central opening sized to engage with an interference fit a tube or pipe passing through the device. Alternatively, the ring can support a tube coupling for providing a tubular connection within the device to receive and couple pipes on opposite sides of the building wall or floor in which the device is installed.

U.S. Pat. No. 5,417,019, issued May 23, 1995 to Marshall et al., shows a coupling device for installation in a building wall or floor to provide a passthrough opening for pipes, tubing, and the like comprises an axially elongated, plastic tubular housing with a radially extending mounting flange and having open first end and a second end which is closed by a transverse wall. At least one tubular coupling element having an entrance end and an exit end is positioned within the housing to extend axially thereof with the entrance end of the coupling opening to the first end of the housing. Intumescent firestop material surrounds the coupling element and fills the space between the coupling element and the outer housing. A tube member extends from the coupling element to the second end of the housing. After the coupling device is installed, the second end of the housing is cut away at the surface level of the partition to expose the tube member for connection to the associated piping system.

U.S. Pat. No. 4,136,707, issued Jan. 30, 1979 to Gaillot et al., is for an annular case having a first portion which projects from the wall and a second portion which is embedded in the wall. A tubular element connected to two pipes of the piping defines a passage through the case. The tubular element has a first section and a second section respectively located in the first portion and second portion of the case. The tubular element is of a material which is rigid at ordinary temperature and softens under the action of heat. At least the first section is of a fusible material having a distinct point of fusion. The first portion of the case is provided with means for instantaneously closing the passage as soon as the first section has disappeared. The second portion of the case is filled with a material which swells radially under the action of heat.

Whit is needed is a document depository or mail slot through a wall which is lined with intumescent material that expands from the heat of a fire to seal the slot and prevent the spread of the fire through the slot in the wall and preferably an adjustable size wall slot.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a document depository or mail slot through a wall which is lined preferably on a top wall of the slot with intumescent material that expands from the heat of a fire so that the top wall intumescent material expands downwardly to the bottom wall of the slot to seal the slot and prevent the spread of the fire through the slot in the wall thereby providing a fire rated mail and document slot which can be built into a fire rated wall.

Another object of the present invention is to provide a smoke shield flap of flexible fabric material which hangs down within the slot from the top wall to the bottom wall at any desired location in the slot to prevent the passage of smoke through the slot while allowing documents to pivot or push the smoke shield flap aside easily as the documents pass through the slot.

One more object of the present invention is to provide an adjustable wall passthrough slot to fits walls of various thicknesses and accommodate materials of various sizes to pass through.

A related object of the present invention is to provide a wall passthrough slot which is easily installed by attaching each of two separate halves of the slot to opposite sides of the wall interconnecting the two halves to form a slot of a desired slot size with a frame around the slot on each side screwed into one side of the wall.

In brief, after forming an appropriately sized opening through a wall, the two halves of the slot are interconnected through the opening and each half is screwed into one side of the wall through a frame surrounding the slot opening. One half of the slot structure forms one side of the slot formed by the upper inside surface of the slot having an upwardly inclined inner surface coated with an intumescent layer extending from the bottom of the frame. The other half of the slot structure forms the bottom side of the slot formed by the lower inside surface of the slot having an downwardly inclined inner surface. The two inclined surfaces are positioned in parallel spaced apart by the desired thickness of the slot.

A smoke shield flap of flexible fabric material hangs down within the slot from the top wall to the bottom wall at any desired location in the slot to prevent the passage of smoke through the slot while allowing documents to pivot or push the smoke shield flap aside easily as the documents pass through the slot.

An advantage of the present invention is that it prevents the spread of fire through a wall passthrough slot.

Another advantage of the present invention is that it prevents the spread of smoke through a wall passthrough slot.

One more advantage of the present invention is that it provides a wall passthrough slot that is adjustable to fit different wall sizes and accommodate different sizes of material through the slot.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other details of my invention will be described in connection with the accompanying drawings, which are furnished only by way of illustration and not in limitation of the invention, and in which drawings:

FIG. 1 is a cross-sectional view through the fire rated adjustable wall passthrough slot device of the present invention with the device positioned in a fire rated wall under normal conditions for passing mail and paperwork through the slot;

FIG. 2 is a cross-sectional view of the slot device of FIG. 1 with the device positioned in a fire rated wall under the conditions of a fire showing the intumescent material expanded by the heat of the fire to block the slot and prevent the fire spreading from one side of the wall to the other;

FIG. 3 is an exploded perspective view of the two slot forming components of the wall passthrough slot of FIG. 1 which overlap and connect to the two sides of a pre-formed wall opening to form the wall passthrough slot;

FIG. 4 is a schematic side elevational view of the two slot forming components of the wall passthrough slot aligned for interconnecting in an overlapping relationship to form the wall passthrough slot of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

In FIGS. 1-4, a fire rated wall passthrough slot device 20 for passing mail and paperwork 30 preferably into a collection box 32 through a pre-formed wall opening in a fire rated wall 40 is installed in two overlapping slot forming components 10A and 10B.

A series of slot surfaces 27, 28, 26A and 26B interconnect peripherally to form a passageway between the slot surfaces in the form of a slot 22 having an opening on each of two opposing ends of the slot roughly coinciding with each of the two sides of the wall 40. The slot 22 extends through the wall 40 from one side of the wall to the other side of the wall so that the slot acts as a passageway for mail and paperwork 30 passed through the opening in the wall from one side of the wall to the other side, of the wall.

At least one layer of intumescent material 24 is attached by edge flanges 11 (FIGS. 1 and 2) with the intumescent material 24 slid in from an open side or by an adhesive (FIGS. 3 and 4) or by pegs or screws 18 (FIG. 1A) preferably to a top slot surface 27. In FIG. 3, there may be an additional or alternate layer of intumescent material 24A on a bottom slot surface 28. The layer of intumescent material 24 or 24A is attached to a portion or all of the slot surface 27 or 28 so that the intumescent material 24 and 24A does not interfere with the passage of mail and paperwork 30 through the slot 22 under normal environmental conditions, as in FIG. 1, and so that, in the event of a fire 60 as in FIG. 2, the layer of intumescent material 24 is expandable by the heat of the fire 60 to fill the passageway 22 with expanded intumescent material 24 to close the slot 22 and prevent the spread of the fire 60 through the slot 22.

The device of claim 1 further comprising a smoke shield flap 25 of flexible material hanging down within the slot from the top slot surface to the bottom slot surface at any desired location in the slot to prevent the passage of smoke through the slot 22 while allowing mail and documents 30 to pivot or push the smoke shield flap aside easily as the mail and documents 30 pass through the slot 22.

A means to adjust the device to fit walls 40 of various thicknesses comprises at least two slot forming components 10A and 10B interconnectable through a pre-formed wall opening of a fire rated wall 40 in an adjustable overlapping relationship, each of the. slot forming components comprising at least one of the series of slot surfaces 27, 28, 26A and 26B, the slot forming components adjustable to extend through any of a number of walls of varying wall thickness from one side of a wall.

A peripheral frame 21A and 21B on each slot forming component 10A and 10B extends peripherally beyond the pre-formed opening in the wall 40 and attaches to one side of the wall by an adhesive, screws or other conventional means. An outside cosmetic frame may also snap over the attached frame 21A and 21B to cover the screws if screws are used to secure the attached frame 21A and 21B to the wall 40.

Furthermore, a means to adjust the height of the slot to accommodate mail and paperwork 30 of any of a variety of sizes may also comprise the first slot forming component 10A comprising a first side slot surface 26A and an upper slot surface 27 inclined downwardly from an outside of the wall to an inside of the wall and no side surface on the opposing side enabling the intumescent material 24 to slide in or otherwise be installed on the upper slot surface 27, and the second slot forming component 10B comprising a second side slot surface 26B to form the other side of the slot where there is no side on the first slot forming component 10A and no side surface where the first slot forming component has the other side slot surface 26A and a bottom slot surface 28 inclined downwardly from an outside of the wall to an inside of the wall, the two slot forming components 10A and 10B being movable in an overlapping interrelationship to adjust the top and the bottom slot surfaces 27 and 28 to be positioned in a parallel relationship spaced apart by a desired height of the slot 22. There are also overlapping top flanges 29A and 29B and overlapping bottom flanges 23A and 23B on the two slot forming components 10A and 10B as well as an optional flat surface 19 adjacent to the receiving box 32.

In use, the layer of intumescent material 24 does not interfere with the passage of mail and paperwork 30 through the slot under normal environmental conditions, as in FIG. 1. In FIG. 2, in the event of a fire 60, the layer of intumescent material 24 expands due to the heat of the fire to fill the passageway 22 with expanded intumescent material 24 to close the slot 22 and prevent the spread of the fire 60 through the slot 22.

The smoke shield flap 25 of flexible material hangs down within the slot 22 from the top slot surface 27 to the bottom slot surface 28 at any desired location in the slot 22 to prevent the passage of smoke through the slot 22 while allowing mail and documents 30 to pivot or push the smoke shield flap 25 aside easily as the mail and documents 30 pass through the slot 22.

The two slot forming components 10A and 10B are preferably fabricated of heavy sheet metal or other fireproof material.

It is understood that the preceding description is given merely by way of illustration and not in limitation of the invention and that various modifications may be made thereto without departing from the spirit of the invention as claimed. 

1. A fire rated wall passthrough slot device for passing mail and paperwork through a wall opening, the device comprising: a series of slot surfaces interconnected peripherally to form a passageway between the slot surfaces in the form of a slot having an opening on each of two opposing ends of the slot, the slot extending through the wall from one side of the wall to the other side of the wall so that the slot acts as a passageway for mail and paperwork passed through the opening in the wall from one side of the wall to the other side of the wall; at least one layer of intumescent material attached to at least one of the slot surfaces so that the intumescent material does not interfere with the passage of mail and paperwork through the slot under normal environmental conditions and so that, in the event of a fire, the at least one layer of intumescent material is expandable due to the heat of the fire to fill the passageway with expanded intumescent material to close the slot and prevent the spread of the fire through the slot.
 2. The device of claim 1 further comprising a smoke shield flap of flexible material hanging down within the slot from the top slot surface to the bottom slot surface at any desired location in the slot to prevent the passage of smoke through the slot while allowing documents and mail to pivot or push the smoke shield flap aside easily as the documents and mail pass through the slot.
 3. The device of claim 1 further comprising a means to adjust the device to fit walls of various thicknesses.
 4. The device of claim 3 wherein the means to adjust the device to fit walls of various thicknesses comprises at least two slot forming components interconnectable through a pre-formed wall opening in an adjustable overlapping relationship, each of the slot forming components comprising at least one of the series of slot surfaces, the slot forming components adjustable to extend through any of a number of walls of varying wall thickness from one side of a wall.
 5. The device of claim 4 wherein each of the slot forming components further comprises a peripheral frame extending beyond the pre-formed opening in the wall, the peripheral frame attachable to one side of the wall.
 6. The device of claim 1 further comprising a means to adjust the height of the slot to accommodate mail and paperwork of any of a variety of sizes.
 7. The device of claim 6 wherein the means to adjust the height of the slot to accommodate mail and paperwork of any of a variety of sizes comprises a first slot forming component comprising a first side surface of the slot and an upper surface of the slot inclined downwardly from an outside of the wall to an inside of the wall and a second slot forming component comprising a second side surface of the slot and a bottom surface of the slot inclined downwardly from an outside of the wall to an inside of the wall, the two slot forming components movable in an overlapping interrelationship to adjust the top and the bottom slot surfaces to be positioned in a parallel relationship spaced apart by a desired height of the slot.
 8. An adjustable size wall passthrough slot device for passing mail and paperwork through a wall opening, the device comprising: at least two slot forming components interconnectable through a pre-formed wall opening in an adjustable overlapping relationship, each of the slot forming components comprising at least one of a series of slot surfaces interconnected peripherally to form a passageway between the slot surfaces in the form of a slot having an opening on each of two opposing ends of the slot, the slot extendable through any of a number of walls of varying wall thickness from one side of a wall to another side of the wall so that the slot acts as a passageway for mail and paperwork to be passed through the opening in the wall from one side of the wall to the other side of the wall, a first slot forming component comprising a first side surface of the slot and an upper surface of the slot inclined downwardly from an outside of the wall to an inside of the wall and a second slot forming component comprising a second side surface of the slot and a bottom surface of the slot inclined downwardly from an outside of the wall to an inside of the wall, the two slot forming components movable in an overlapping interrelationship to adjust the top and the bottom slot surfaces to be positioned in a parallel relationship spaced apart by a desired thickness of the slot.
 9. The device of claim 8 further comprising at least one layer of intumescent material attached to at least one of the slot surfaces so that the intumescent material does not interfere with the passage of mail and paperwork through the slot under normal environmental conditions and so that, in the event of a fire, the at least one layer of intumescent material is expandable due to the heat of the fire to fill the passageway with expanded intumescent material to close the slot and prevent the spread of the fire through the slot.
 10. The device of claim 8 further comprising a smoke shield flap of flexible material hanging down within the slot from the top slot surface to the bottom slot surface at any desired location in the slot to prevent the passage of smoke through the slot while allowing documents and mail to pivot or push the smoke shield flap aside easily as the documents and mail pass through the slot.
 11. The device of claim 8 wherein each of the slot forming components further comprises a peripheral frame extending beyond the pre-formed opening in the wall, the peripheral frame attachable to one side of the wall. 